An allograft includes bone, tendon, skin, or other types of tissue that is transplanted from one person to another. Allografts are used in a variety of medical treatments, such as knee replacements, bone grafts, spinal fusions, eye surgery, and skin grafts for the severely burned. Allografts come from voluntarily donated human tissue obtained from cadaveric donor-derived, living-related, or living-unrelated donors and can help patients regain mobility, restore function, enjoy a better quality of life, and even save lives in the case of cardiovascular tissue or skin.
Processing operations for osseous-based allografts often require the removal of articular cartilage from donated human cadaveric femoral heads. Operations also often involve the removal of outer layers of harder cortical bone to expose the more delicate cancellous bone required for an osseous-tissue donation beneath.
Currently, the removal of superficial cartilage and cortical bone layers from the articular surface of a cadaveric human femoral head occurs via one of three methods. The first method involves manually exposing the articular surface of the femoral head to a rotating, half-spherical steel drill bit having sharp cutting surfaces embedded within the sphere's interior dome. The bit also features a sharp, serrated edge that rims the circular, outside edge of the bit. The configuration of the rotating bit, when manually introduced to the articular surface, serves to abrade or strip the cartilage and outer bone layers from the femoral head. The second method involves a manual process whereby a technician repeatedly passes a sharp-edged gouge over the articular surface of the femoral head to remove the cartilage/bone layers in thin strips. The third and primary method of processing the articular surface involves introducing the femoral head into the sharp edge of a band-saw blade to remove the articular cartilage and cortical bone layers, again in thin strips.
Each of the current processing methods for preparing donated human cadaveric femoral heads presents significant drawbacks in the form of inherent risks to the operating technician and to the osseous tissue being processed. Existing hand tools used to prepare and process osseous-based allografts are not designed to safely process the non-uniform, asymmetrical contour of human femoral heads. For example, the drill bit method carries a risk of vibration-related injuries to the operator, while the gouge method carries risks of musculoskeletal injury due to the repetitive hand, wrist, shoulder, and arm motions required during processing. The band saw method carries traumatic laceration risks to the operator's hands and/or fingers, which are placed in the path of the band-saw blade. Without highly skilled technicians, all of the current methods present a risk of damage to the femoral head's underlying cancellous tissue. Moreover, all of the current methods are time consuming and inefficient, regardless of technician skill and/or experience level.